1. Field of the Invention
The present invention relates to a gas purge apparatus, a load port apparatus, and a gas purge method.
2. Description of the Related Art
For example, manufacturing process of semiconductors includes the following technique (bottom purge): a gas purge nozzle is arranged on an installation stand of a load port apparatus and is made contact with a gas purge port provided at a bottom part of a wafer transport container to introduce a purge gas therethrough and clean the inner atmosphere of the wafer transport container by the purge gas.
Upon performing the bottom purge, the purge nozzle is moved toward the purge port to contact with the gas purge port provided at the bottom part of the wafer transport container to be purged (e.g., Patent Document 1). In this time, a plurality of the purge ports provided at the bottom part of the container may be pushed up by the purge nozzle, and the container may lean.
When the container leans, handling performance of wafers is deteriorated. For example, the following problems arise: the wafers placed on a shelf inside of the container lean and may be damaged; the purge gas may be leaked due to insufficient contact between the purge port and the purge nozzle; and the outside gas may flow into the container.
Patent Document 1: Japanese Patent Laid-Open No. 2003-60007